反応 #12012

反応方程式

water

(4R,9aR)-6-bromo-4-methyl-3,4,9,9a-tetrahydro-1H-2,4a,5-triaza-fluorene-2-carboxylic acid tert-butyl ester

intermediate b

(4R,9aR)-6-bromo-4-methyl-3,4,9,9a-tetrahydro-1H-2,4a,5-triaza-fluorene-2-carboxylic acid tert-butyl ester

triethylborane

potassium carbonate

triethylborane

→

product

収率 89.5%

(4R,9aR)-6-Ethyl-4-methyl-3,4,9,9a-tetrahydro-1H-2,4a,5-triaza-fluorene-2-carboxylic acid tert-butyl ester

収率 89.5%

溶媒

N,N-dimethylformamide

THF

反応条件

後処理

1. 1
   抽出extracted twice with ethyl acetate
2. 2
   洗浄The combined organic phases were washed with brine
3. 3
   乾燥dried over magnesium sulfate
4. 4
   ろ過filtered
5. 5
   その他evaporated
6. 6
   その他The crude product was purified by column chromatography on silica gel (Q0.032–0.063 mm) with tert-butyl methyl ether:n-hexane (1:4) as eluant

実験手順

To a solution of 0.70 g (1.90 mmol) (4R,9aR)-6-bromo-4-methyl-3,4,9,9a-tetrahydro-1H-2,4a,5-triaza-fluorene-2-carboxylic acid tert-butyl ester (Example 5, intermediate b) in 14 ml N,N-dimethylformamide was added 73.0 mg [1,1′-bis(diphenyphosphino)ferrocene]-dichloropalladium(II) and after 15 min, 4.8 ml of a 1M triethylborane solution in THF and 0.79 g (5.70 mmol) potassium carbonate were added. After 4 h another 2.4 ml triethylborane solution was added and the reaction mixture stirred overnight at 65 deg C. The mixture was cooled to room temperature and the suspension was poured into water and extracted twice with ethyl acetate. The combined organic phases were washed with brine, dried over magnesium sulfate, filtered and evaporated. The crude product was purified by column chromatography on silica gel (Q0.032–0.063 mm) with tert-butyl methyl ether:n-hexane (1:4) as eluant to yield the product as a colorless oil (89.5%).

出典